Electronic Control Unit (Ecu)

Perform SPARK TEST check. If secondary spark is present, ignition control unit is okay. If not, turn ignition off. Disconnect ignition control unit wire harness connector. Turn ignition on. Using a voltmeter, measure voltage between terminal No. 2 (-) and terminal No. 4 (+) of connector. See Fig 1 .
Voltage should be present. If not, ensure continuity exists between terminal No. 2 and ground. Continuity must also exist between terminal No. 4 and ignition coil positive terminal. Repair wiring if necessary. If wiring is okay, replace ignition control unit.

Fig 1: Checking Typical Ignition Control Unit Voltage

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NOTE: These tests require a high-impedance volt-ohmmeter.